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911.
As an important component of sustainable development in mountain areas, evaluation for sustainable land use is always one
of the hotpots of researches on sustainable development. Traditional evaluation for sustainable land use mainly focuses on
the sustainability of land use model and biological production on temporal scale, and overlooks the effects of land use patterns
on the sustainability, while landscape ecology can be a good help to realize the spatial analysis of sustainable land use.
In this study, a synthetic evaluation indexes system for sustainable land use was constructed through the application of landscape
metrics. Taking Yongsheng County of Yunnan Province, China as a case study, a series of quantitative evaluation were conducted
in 1996, 1999 and 2001, to monitor the temporal dynamics of regional land use sustainability. Two indicators, contributing
amount of indexes, and obstacle amount of indexes, were also set up to ascertain the significance of all the evaluation indexes
to the evaluation results. The results showed that, in the study phases, the land use sustainability of the whole county had
been low with a stable but great spatial difference, and great changes took place in regional land use system in 1999 with
the deviation from the aim of sustainable land use. It also showed that, the most important indexes contributing for the land
use sustainability in the study period, were the indexes of population density and land use degree, followed by the index
of landscape diversity and cropping index. And the most important indexes counteracting the land use sustainability were the
indexes of per unit area total production value of industry and agriculture, per unit area yield of cereal crops, landscape
fragmentation, followed by the indexes of per unit area yield of economic crops and fertilizer consume per unit area. 相似文献
912.
Faecal coliform (FC) levels in surface water and clams (Ruditapes decussatus) and variations in environmental parameters were studied in two bivalve harvesting areas in the Alvor lagoon (southern Portugal).
Land use and cover characteristics in adjacent subwatersheds were also analysed to assess their contributions as sources of
faecal contamination. High FC levels in clams from the harvesting area in the most urbanized subwatershed (impervious surface
coverage ≈ 10.5%) were positively associated with rainfall and with the cooler periods of the year. FC levels in clams from
the least urbanized subwatershed were generally very low and did not present any detectable seasonal trend. From these results,
it was concluded that the periodic deterioration of the microbiological quality of clams derives from the cumulative impact
of the reservoir of faecal contamination created in urbanized areas, entering into the lagoon during storm water runoff. 相似文献
913.
中国西部城市化基本特征分析——以新疆为例 总被引:2,自引:0,他引:2
孙建丽 《中国人口.资源与环境》2000,10(4):54-57
本文以新疆为例,探讨了新疆城市化的基本特征和规律,总结经验教训,以朝正确认识西部地区城市化的基本特征,从而为西部大开发中城市化发展战略的制定提供有价值的借鉴和参考。 相似文献
914.
环渤海地区500年来的旱涝变化及其区域分异 总被引:2,自引:0,他引:2
用研究区1470~1985年的旱涝等级资料,划分了该地区500年来旱涝变化的7个阶段,讨论了不同阶段间旱涝型的变化及其旱涝型区域分异意义。结果表明,500年来研究区有4类主要旱涝型,各型旱涝在不同阶段的重要程度及场型特征有较大差异,深刻反映了该地区500年来旱涝区域分异特征的变化。通过对500年来旱涝变化与温度变化的对比发现,较温暖期,研究区的旱涝型及旱涝区域分异格局较多变,旱涝变化的区域差异性较 相似文献
915.
Marine protected areas (MPAs) are considered as a valid tool for mitigating the impact of fishing on marine ecosystems. Their success depends upon their acceptance by implicated stakeholders and on the integration of the stakeholder groups into their management. This integration is especially important with regard to fishermen, whose interests are the most directly affected by MPAs. The relational coordination method posits that effective communication and supportive relationships among stakeholders result in positive stakeholder behaviors and a more effective management of the system. Applying its principles, we designed a survey to evaluate the satisfaction of fishermen associated with five MPAs in the Spanish Mediterranean and determine what mechanisms affect fishermen’s acceptance of MPAs. Our results demonstrate that effective communication is particularly important for good supportive relationships and satisfaction among fishermen and other stakeholder groups, as well as satisfaction with the MPA. Sharing objectives with fishermen through timely communication is the primary mechanism to improve fishermen''s satisfaction and ameliorate perceptions towards MPA. To address this issue, we recommend more substantial integration of fishermen in the co-management of MPAs. 相似文献
916.
Marine protected areas (MPAs) have become a key component of conservation and fisheries management to alleviate anthropogenic pressures. For MPA networks to efficiently promote persistence and recovery of populations, ecological connectivity, i.e. dispersal and movement of organisms and material across ecosystems, needs to be taken into account. To improve the ecological coherence of MPA networks, there is hence a need to evaluate the connectivity of species spreading through active migration and passive dispersal. We reviewed knowledge on ecological connectivity in the Baltic Sea, Kattegat and Skagerrak in the northeast Atlantic and present available information on species-specific dispersal and migration distances. Studies on genetic connectivity are summarised and discussed in relation to dispersal-based analyses. Threats to ecological connectivity, limiting dispersal of populations and lowering the resilience to environmental change, were examined. Additionally, a review of studies evaluating the ecological coherence of MPA networks in the Baltic Sea, Kattegat and Skagerrak was performed, and suggestions for future evaluations to meet management needs are presented.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-021-01684-x. 相似文献
917.
黄土丘陵沟壑区农村特色生态经济模式探讨——以陕西绥德县为例 总被引:11,自引:0,他引:11
黄土丘陵沟壑区是我国北方生态脆弱、产业单一、广种薄收、乡村贫困的特殊问题区域。“越穷越垦、越垦越穷”的土地利用方式成为统筹人与自然和谐发展的关键“瓶颈”。论文运用农业地理学和生态经济学原理,以绥德县为典型案例区,进行了农村经济社会发展主要的限制因素剖析。认为该区土地资源利用必须正确处理宏观与微观效益的关系,加强水土保持、生态建设与脱贫解困目标的有机结合。依据研究区地形地貌特点与水土流失规律,重视旱作农业与节水灌溉技术、示范推广造林实用技术、水保型生态农业技术的创新与应用,大力发展柠条防护林产业化、水保型立体农业、生态资源开发增效等典型农村特色生态经济模式。 相似文献
918.
中国西部贫困地区可持续发展研究 总被引:22,自引:2,他引:20
赵曦 《中国人口.资源与环境》2001,11(1):82-86
本文探讨了贫困与可持续发展的相互关系。在系统阐释中国西部贫困地区可持续发展面临的现实问题、困难和障碍的基础上,着重围绕西部贫困地区可持续发展的基本内容和实施途径进行了综合性的分析和研究。 相似文献
919.
The aim of this study was to quantify the diffuse emissionsduring use of metal containing goods in the capital of Sweden,Stockholm. The following metals were studied: Cadmium (Cd), Chromium (Cr), Copper (Cu), Lead (Pb), Mercury (Hg), Nickel (Ni) and Zinc (Zn).A major part of the metals are found in a protected environmentwhere degrading processes like corrosion are most limited. However, during the lifetime of some goods the metal release to the environment is significant. The quantitatively most dominant emissions were found for Cu and Zn. The tap water system and roofs/fronts (Cu) represent goods with large exposedareas but with relatively small release rates per unit. In contrast, brake linings, aerial lines and electrical grounding (Cu) and tyres, brake linings and chemicals (Zn) are allgoods with high release rates but mostly limited exposed stocks.High yearly emissions are also found for Pb, ammunition andsinkers dominate the calculated emissions totally. For Cr and Ni, stainless steel represent the major part of the stocks, butcorrosion was estimated to give only a minor contribution to the emissions. Potential emission sources, i.e. stabilisers,pigments and plated goods dominate the exposed Cd stock. Theseemissions were not quantified due to lack of data. Hg is currently phased out, but one major source of emission, i.e. the use of amalgam, will be continuously significant for several decades. The importance of the traffic sector is obvious. The emissionsfrom brake linings (Cu, Zn and Pb), tyres (Zn, Pb, Cr and Ni)and asphalt wear (Cu, Zn, Cr, Ni and Pb) are all of large importance for the total emission from respectively metal. 相似文献
920.
Effects of Local Land Use on Physical Habitat, Benthic Macroinvertebrates, and Fish in the Whitewater River, Minnesota, USA 总被引:7,自引:0,他引:7
Best management practices (BMPs) have been developed to address soil loss and the resulting sedimentation of streams, but information is lacking regarding their benefits to stream biota. We compared instream physical habitat and invertebrate and fish assemblages from farms with BMP to those from farms with conventional agricultural practices within the Whitewater River watershed of southeastern Minnesota, USA, in 1996 and 1997. Invertebrate assemblages were assessed using the US EPA's rapid bioassessment protocol (RBP), and fish assemblages were assessed with two indices of biotic integrity (IBIs). Sites were classified by upland land use (BMP or conventional practices) and riparian management (grass, grazed, or wooded buffer). Physical habitat characteristics differed across buffer types, but not upland land use, using an analysis of covariance, with buffer width and stream as covariates. Percent fines and embeddedness were negatively correlated with buffer width. Stream sites along grass buffers generally had significantly lower percent fines, embeddedness, and exposed streambank soil, but higher percent cover and overhanging vegetation when compared with sites that had grazed or wooded buffers. RBP and IBI scores were not significantly different across upland land use or riparian buffer type but did show several correlations with instream physical habitat variables. RBP and IBI scores were both negatively correlated with percent fines and embeddedness and positively correlated with width-to-depth ratio. The lack of difference in RBP or IBI scores across buffer types suggests that biotic indicators may not respond to local changes, that other factors not measured may be important, or that greater improvements in watershed condition are necessary for changes in biota to be apparent. Grass buffers may be a viable alternative for riparian management, especially if sedimentation and streambank stability are primary concerns. 相似文献